Til Death
by The-stuttering-kiwi
Summary: Requested one-shot. Sigyn joins Loki in his punishment after a failed plan to kill Odin. Will Thor be able to convince his little sister to leave Loki to his fate and save herself? AU where Thor and Loki are not brothers. More norse mythology than MCU.


Thor couldn't believe what he was seeing. The moon he was standing on, the once smooth surface was now riddled with canyons, the cliffs had crumbled to nothing, and the ruins of an ancient civilization turned to dust. Had it really been that long since he locked Loki away to his sentence deep below the ground? He could care less if this piece of rock disintegrated into atoms and took Loki with it—but his little sister-he had to get her out of here.

* * *

"It's getting full." Sigyn said worriedly, looking at the wooden bowl in her hands, hands that had grown used to the strain of her task they were numb to the weight.

Loki merely groaned in response. _Full already_?

His eyes traveled upwards to the snake looming above their heads and watched as a fresh bead of venom formed on the tip of its fangs. When it finally dripped into the bowl it almost spilled over the sides, dangerously close to Sigyn's fingers.

"Dump it."

"But you aren't even healed…" She stared at his blistered chest, knowing the venom would hurt worse going into the open wounds.

"I never am." He steadied himself against the rock at his back, gripped the extra slack of the chain that held him to it; his only hope is that it would hold him still but it never did, "Dump it."

* * *

The force of the tremors nearly knocked Thor off his feet. The roar of the ground cracking was deafening, he was nearly crushed when a boulder broke away from the stone formation above him. It was going to take hours for him to find the entrance to the cave as all the landmarks had been destroyed, and that was if it wasn't caved in.

Guilt squeezed his throat like a vice. How could he have let Sigyn join Loki in his punishment?

* * *

Sigyn dumped the venom as quick as she could, careful not to let any splash back on to her legs, while Loki screamed and writhed behind her. Dirt, dust, and bits of rock rained down on them, Sigyn squeezed her eyes shut to keep out the debris. When she put the bowl back over Loki's chest the tremors slowed to a stop.

"I'm…sorry," Loki panted, his black hair plastered to the side of his face from sweat, "I shouldn't have let you come."

"It's not like you could have stopped me."

"Thor could have." Loki's locked eyes with hers.

"But he didn't." She replied matter-of-factly.

* * *

Thor cursed himself with every step he took, as he had every day since Loki's trial. The court had found Loki guilty within moments—a plan to kill the Allfather—and he was a hair's breadth away from carrying it out. What Thor hadn't counted on was as Loki was being dragged away in chains was his sister calling guilt on herself to be with him. He had been embarrassed that Sigyn had a relationship with Loki, every time they flaunted themselves it set his teeth on edge; he was starting to lose respect as Asgard's general.

To this second he wasn't sure if she was really guilty or not but he didn't care at the time. Then he just wanted her out of his hair.

* * *

"I'm not leaving." Sigyn's grip tightened, her sweaty palms making the bowl slip around in her hands.

"Sigyn…"

"I _chose_ to be here with _you_. Did you really think I would have let you go through this alone?"

"You are in danger here." Loki's eyes flicked up to the snake looming overhead. He had to hand it to Thor, this was an interesting punishment.

"I've been in danger ever since I've met you, I don't see why this is any different," Sigyn remembered the first time she saw Loki...she was hooked almost immediately. Her brother nearly lost his mind when he first caught them together, Thor had forbidden them from being together but that didn't stop them from getting married in secret.

"Not like this. Look at the damage in here; I can only imagine what it looks like on the surface."

Sigyn couldn't deny that. The cracks in the walls were deep, rubble was piled around them—it wouldn't be long before they were crushed themselves.

* * *

Thor's arms were exhausted as he lifted boulder after boulder away from the entrance of the cave. As he neared the bottom of the pile he saw a glint of Asgardian gold amour and felt his stomach churn dangerously for the guard who didn't leave his post even to save himself.

* * *

"I don't regret being here with you." Sigyn said firmly.

"I do," But when Loki saw a flicker of hurt cross her face he clarified, "I don't regret anything with you. I do wish I hadn't let you come here, you didn't know anything about my plan."

"If I had I would have stopped you."

"Because he's your father," Loki spoke the doubt that caused him to keep his plan to himself—that made him doubt his wife.

"Odin has never been a father to me—he has been obsessed with Thor since the day he was born. Why do you think he didn't care that we were married. I wouldn't have stopped you because he's my father—I would have stopped you to prevent this."

* * *

Thor could hear murmuring a bit farther ahead, he knew he was close, he wondered what it would take to pull his sister away. He wondered if Loki wanted her to leave—or if he had made her join him. He wouldn't put it past the bastard.

"It's time to dump the bowl again," He was just able to make out Sigyn's words which meant he was only a few steps away.

He heard Loki murmur a reply, then Loki's screams; Thor hoped he wouldn't be crushed as the ground beneath his feet shook and he was thrown onto the dirt.

* * *

"You're bleeding." Loki croaked.

"I'm fine," Sigyn carefully held the bowl in one hand to wipe the blood out of her eyes. Blinking rapidly, she gently touched the gash on her head and felt her stomach lurch—she hoped she wouldn't pass out.

"You can't stay here," Even though Loki was weak she had never heard him be more firm.

"He's right—you are leaving. Now."

The bowl almost slipped from Sigyn's hands.

* * *

Thor wasn't sure what he had expected as he took in the scene before him. Loki chained to a large rock, with the enormous snake looming above him, the plink as each drop of venom was caught in the bowl in his sisters' hands. Her eyes, large and unblinking—he wasn't sure how well she was able to see with the steady stream of blood running down her face and trickling into her eyes—her mouth hanging open in surprise. And Loki, chest crackled and blistered, looking at Thor with blatant amusement.

"What are you doing here?" Sigyn demanded, she was glad she sounded stronger than she felt—at that moment she felt light-headed.

"I'm here to take you home."

"I'm not going home."

"Yes, you are." Thor and Loki said in unison.

Sigyn looked back and forth from her brother and her husband.

"How quickly can you get her out of here?" Loki asked, ignoring Sigyns protests.

"It might take time if the tunnel has collapsed anymore. As soon as I get her to surface I can call Heimdal to take us home."

"Put the bowl in my chest, you just emptied it; it will give you enough time to leave," Loki locked eyes with Sigyn who seemed to choke on her words.

"I…I'm not…"

"Yes, you are!" Thor roared, "Sigyn, I didn't stop you from coming, but Norns help you if you think I am leaving you here."

"I am not leaving Loki just to ease your guilt." She spat back, "Or yours," She spoke more gently to Loki, "I love you, I am not leaving."

"We are wasting time! The tunnel may not survive another tremor!"

"Then you should go!"

The next moment passed in slow motion as Thor moved forward to grab Sigyn's shoulders—he thought maybe he could shake some sense into her. But the only sound that was heard was Sigyn's shriek as the bowl was knocked from her hands—and the echo as it shattered on the ground.

Blood thundered in Sigyn's ears in time to the pounding tempo of her heart—her eyes slowly trailed upwards to see the next bead of venom form on the tip of the snake's fangs. She didn't hesitate as she threw herself over Loki's chest.

Thor was frozen as he watched his sister scream and writhe—Loki's screams mingled with hers as the venom rolled off her back and on to his skin. The snake—agitated by the extra noise twisted and spit—somehow producing more venom than before.

He wasn't sure what to do—but then everything went black.

* * *

Thor grunted with the effort of shifting rubble.

"Sigyn, please be alive." He prayed each time he moved a boulder—until he moved one that had a smear of blood on the underside.

He knew what he would find before he moved the last piece of stone.

Sigyn was still draped over Loki—who had broken the free of the chains to try and protect his wife but it was too late…too late for either of them.


End file.
